The secret couple spent some time off the grid together, surfing sand dunes and soaking up the sun, just weeks before Chris strangled wife Shan'ann Watts, smothered his 4- and 3-year-old daughters, buried Shan'ann in a shallow graves and dumped his kids' bodies in oil tanks.

The flirty videos were uncovered by HLN for an episode of its "Lies, Crimes and Video" series, "Killer Dad: Chris Watts Speaks."

HLN also uncovered giggly voicemails that Kessinger left for Chris. "Hi, it's me. I miss your face. Call me when you can, I guess," she says in one.

Chris pleaded guilty to murdering his family, and he is serving multiple life sentences behind bars. Kessinger told police she had no idea Chris would kill his wife and children and has cut off all ties with him.